Hydraulic applications are applications which include movement of a working fluid which is pressurized relative to ambient pressure. These applications include petrochemical or chemical processing, oil refinement, and hydraulically operated implements (e.g., vehicle braking systems, hydraulic jacks, garbage compactors, pneumatic drills, etc.) among others. Working fluids, also known as process fluids, are typically chemical solutions, oils or other petroleum products, water or water based solutions, as well as other liquid materials. In many hydraulic applications, a steady fluid pressure is required to satisfy the needs of the application process. Unwanted pressure fluctuations often occur in these working fluids due to process variables, pumping inconsistencies, and valve actuation.
In known hydraulic applications, such as the ones mentioned above, an accumulator is used to dampen the pressure fluctuations. An accumulator can include a plunger located within a chamber and in fluid communication with the working fluid. The plunger is biased towards the working fluid by a biasing member (e.g., a compressible gas, a spring, etc.). The biasing member compresses and expands in response to the pressure fluctuations, thereby dampening the fluctuations within the working fluid. However, these accumulators must be adjusted to the average pressure of the process fluid. Additionally, many accumulators do not offer a constant compensation pressure due to the characteristics of springs and compressed gasses. As such, the effectiveness of these accumulators is reduced with large pressure fluctuations and may not satisfy the requirements of a constant pressure process.